Service

What is the Camshaft Position Sensor all about?

The camshaft position sensor monitors the position of the camshaft and reports that data to the car’s onboard computer system. This computer system works with sensors and other devices to keep the engine running. With data from the camshaft position sensor (CPS), the fuel injectors know when to fire.

When the sensor malfunctions, the computer does not know when to fire the injectors and may not fire them at all. The faulty readouts may also throw off spark timing, which will affect the car’s fuel economy. This sensor is used in conjunction with the crankshaft position sensor to control ignition timing. It is common for heat and oil leaks to cause this sensor to fail, due to where the sensor is located.

Keep in mind:

Damage to the camshaft position sensor is often caused by oil leaks; if this is the case, you may need another part of your car replaced or repaired.

When the camshaft position sensor is replaced, the alignment of the timing belt should be monitored so that no fluids leak onto the position sensor mounting area.

Some camshaft position sensors will need to have their software updated when they are installed.

Timing belts, mass air flow sensors, and crankshaft position sensors can all trigger the trouble code for the camshaft position sensor.

How it's done:

Scan test computer for trouble codes.

Pinpoint tests as per flow charts.

Remove and replace Crankshaft Position Sensor.

Clear trouble codes.

Check for proper operation and test drive car.

Our recommendation:

The camshaft position sensor isn’t checked in most regular services, but your vehicle has warning signs for when the sensor begins to fail. Because it sends information to the camshaft, when the sensor begins to fail your engine will begin to have trouble. Your engine may have a hard time turning on, staying on, idling, or running smoothly. Your Check Engine warning light should illuminate as well.

What common symptoms indicate you may need to replace the Camshaft Position Sensor?

Car stalls or does not start.

Car struggles to accelerate (does not maintain speed).

Check Engine light is on.

Car misfires.

Car stumbles or sputters on startup.

Car runs poorly or runs rough.

How important is this service?

The camshaft position sensor provides valuable information about the camshaft position to the computer management system. The computer system uses the information from the position sensor to determine when to inject more fuel. Without the sensor’s information, the computer won’t inject fuel properly, and your vehicle will stall or sputter.